Analysis of antenna-integrated resonant tunneling diodes and its modulation by using adjacent photodiodes for wireless transmitters in radio over fiver technology

We numerically demonstrate a possibility on-off keying (OOK) type of modulation over tens gigabits per second for sub-terahertz radiation by using our proposed wireless transmitter device structure towards radio over fiber (RoF) technology. The integrated device consists of an InP-based compound semiconductor resonant tunneling diode (RTD) adjacent to an InP-based photo diode (PD), a broadband type of bow-tie antenna (BTA), external micro strip lines. These integration structures are carefully designed to obtain high speed and robust relaxation oscillation (RO) due to the negative differential resistance (NDR) characteristic of the RTD and the nonlinearity. Moreover, the device is designed to exhibit OOK modulation of RO to make PD output current inject into the RTD input. Since electromagnetic simulations and equivalent circuit modeling have been basically established for the BTA and the external structure, we perform large signal analysis numerically by simultaneously considering nonlinear circuit model of RTD referring previously reported experimental characteristics of InP-based RTDs.